24th Unterseeboot Flottille

[Stephen67]

Hello All,
I am looking for any help regarding a Kriegsmarine visor cap I have with the former owner's initials labelled inside.
His initials being RH, the cap also has an emblem attached that would appear to indicate 24th U-Flotille. I have been informed he was possibly Verwaltungsoffiziere or Wehrmachtbeamte.
The hat makers label is for Friedrich Methmann mit den Adressen Holm 43 und Norderstraße 81, dated 1936.
Would any forum members know if archives exist covering 24th U-Flotille which could include officials/officers names etc?
Any help would be greatly appreciated.
I do have images but am not sure how to post on here.

[t-geronimo]

Here are those images.